OBJECTIVETo deposit silver nanoparticles on a titanium surface to obtain antibacterial properties. To reduce the incidence of peri-implantitis, and improve the success rate of implantation.

METHODSA silver nanoparticle-modified titanium (Ti-nAg) surface was prepared using silanization method, and its surface was characterized by using X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectrometer (EDX). Two species of bacteria, namely, Staphylococcus aureus and Escherichia coli, were used to test the antibacterial effect of Ti-nAg surface.

RESULTSScanning electron microscope (SEM) revealed that a small quantity of silver nanoparticles were deposited on the titanium surface. XPS analyses revealed that 6.8% of silver was present on the titanium surface. After 24 h of incubation, 94.23% of Staphylococcus aureus and 95.34% of Escherichia coli were killed on the Ti-nAg surface.

CONCLUSIONResults suggest that silver nanoparticle-modified titanium is a promising material with an antibacterial property that may be used as an implantable biomaterial.

Perfofinance of the radio-diagnostic system can be evaluated quantitatively by the analysis method of the ROC curve.Areas under the ROC curves represent the diagnostic perfogrmance efficiency.A comparison of the perforrmance variance of the diagnostic system incurred by different diagnosticians,will find the diagnostic competence of individual diagnosticians.This can help hospital management in deploying personnel in the department of radiology reasonably.

Objective The study was to evaluate DWI for quantifying liver fibrosis. Methods A total of 12 volunteers, 47 patients who had chronic HBV or HCV hepatitis and underwent liver biopsy [Scheuer score for fibrosis(S) and inflammation(G)] were enrolled in this study. They were scanned using a 1.5 T MR unit with b value of 0,250,500,750, 1000 s/mm~2. ADCs at b_(250-1000) and b_(500-1000) were the average ADCs of b=250, 500, 750, 1000 s/mm~2 and b=500, 750, 1000 s/mm~2. The studied the correlation between Scbeuer scores and ADC values, and conducted Mann-Whitney U test and Logistic regression to evaluate ADC for prediction of fibrosis scores. Results The average ADCs were (1.41± 0.11),(1.37±0.09), (1.27±0.05), (1.26±0.04), (1.22±0.06) mm~2/s respectively from SO to S4, stage at b=750 s/mm~2 (F=18.31, P<0.01). With the increase of fibrosis score, the average ADC decreased gradually, the two were better negatively correlated at b_(250-1000)(r=-0.727, P<0.01) than other b values. Using b_(750) and the two combined b values, the found significantly lower ADCs in S2 or greater versus S1 or less and in S3 or greater versus S2 or less fibrosis (P<0.01). The best predictor for S2 or greater was b_(750) with the largest AUC of 0.909, sensitivity of 85.7%, and specificity of 100.0% (ADC ≤1.35×10~(-3) mm~2/s). The best predictor for S3 or greater was b_(250-1000) with the largest AUC of 0.864, sensitivity of 69.6%, and specificity of 95.8% (ADC≤1.53×10~(-3) mm~2/s). Conclusion DWI can be a good predictor for scoring liver fibrosis for S2 or S3 stage above, while b_(750) and the combined b values are suitable for evaluation.

Objective Evaluate the influence of medical monochrome liquid crystal display (LCD) with different resolutions on the detection of pulmonary nodules.Methods Ninety-three direct digital radiography (DR) chest images were selected on-line from picture archiving and communication system (PACS),including 38 positive,32 suspected and 23 normal cases.All of the images were confirmed by CT.These positive images were divided into group A and B according to the diameter of nodules.Three experienced radiologists blindly read the 93 images using three types of displays with different resolutions.Regarding the presence of nodule,five-point confidence system was used:definitely absent,probably absent,indefinite,probably present and definitely present.All observers marked their confidence levels of each image according to the presence of pulmonary nodule on different displays.Software SPSS 13.0 was employed for statistical analysis.Results In the group-A cases,the areas under ROC curves were 0.643,0.686 and 0.739,and in the group-B cases,those were 0.813,0.832 and 0.846 respectively.There was no difference in the detection efficacy among different radiodiagnostic systems.Conclusion Regardless of post-processing tools,it was equivalent to detect pulmonary nodules with different diameters of Group A or B among medical monochrome LCDs with different resolutions.

Objective To investigate the effects of cytokines on the expression of angiotensin Ⅱ type 1 receptor (AT1R) in vascular smooth muscle cells (VSMCs) in rats. Methods Primary cultured VSMCs from SD rat thoracic aorta were cultured in serum-free DMEM for 24 h, and then in DMEM supplemented with 10% fetal bovine serum for another 12 h. The cultured VSMCs were randomly divided into 5 groups (n =6 each): control group (group C); 10% cytokine group (group L); 50% cytokine group (group N); 100% cytokine group (group H) and L-arginine methy ester (L-NAME), an inhibitor of nitric oxide synthase) group. In group C, the cellswere cultured continuously for 12 h. In L, N and H groups, 10%, 50% and 100% cytokines (IL-1β 50 ng/ml +TNF-α 100 ng/ml + IFN-γ 500 ng/ml) were added to the culture medium respectively and the cells were then incubated for 12 h. In group L-NAME, 100% cytokines + L-NAME 5 mmol/L were added to the culture medium and the cells were then incubated for 12 h. The expression of AT1R mPNA and protin was determined by RT-PCR and Western blot respectively.Results Cytokines down-regulated AT1R mRNA and protein expression in a concentration-dependent manner (P ＜ 0.05 or 0.01). L-NAME reversed cytokines-induced changes in AT1R mRNA and protein expression ( P ＜ 0.01). Conclusion Cytokines can down-regulate the expression of AT1R in rat VSMCs and the mechanism is related to the NO synthesis.

It was difficult to prepare traditional Chinese medicine pellets due to the adverse characteristics of the herbal extract. In this study, Danshen extract (DS) powder mixed with different proportions of microcrystalline cellulose (MCC), lactose and starch were made into pellets by extrusion-spheronization. Particle size, span, bulk density, tapping density, compressibility, Hausner ratio and angle of repose were used to evaluate the micromeritic properties of mixing powders. Feret diameter, aspect ratio, yield, density and friability were used to evaluate the properties of the pellets. The correlations between micromeritic properties of raw material powders and the formability of their pellets were analyzed by cluster analysis, principal component analysis and partial least squares regression analysis. As a result, the particle size of the powders was negatively correlated with the size, density, yield, and was positively correlated with the friability of their pellets. The span, density, compressibility and angle of repose of the powders were positively correlated with the size, density, yield, and were negatively correlated with the friability of their pellets. So there were certain correlations between the micromeritic properties of raw material powders and the properties of their pellets prepared by extrusion-spheronization. This research provided a foundation for the technology and method of traditional Chinese medicine extract pellets.
Cellulose ; chemistry ; Drug Compounding ; methods ; Drug Implants ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Excipients ; chemistry ; Lactose ; chemistry ; Medicine, Chinese Traditional ; methods ; Particle Size ; Powders ; chemistry ; Starch ; chemistry

With the content of gallic acid, loganin, paeoniflorin and paeonol as the indexes, to screen out dissolution determination conditions, establish the dissolution determination method for multi-index components in Liuwei Dihuang concentrated pills, calculate and map the accumulative dissolution curve, and then compare the dissolution of products from different pharmaceutical factories through the similarity factor (f2). According to the results, the optimum dissolution determination conditions were the paddle method, with 250 mL 0.1 mol x L(-1) hydrochloric acid as the dissolution medium, and a rotation rate of 100 r x min(-1). The similarity factor values (f2) of the dissolution curves of the four main components of Liuwei Dihuang concentrated pills from different pharmaceutical factories were mostly less than 50. This demonstrated a significant difference in the dissolution of Liuwei Dihuang concentrated pills from different pharmaceutical factories, and provided scientific basis for improving the equality evaluation of Liuwei Dihuang concentrated pills.
Drugs, Chinese Herbal ; chemistry ; Humans ; Organic Chemicals ; analysis ; Quality Control ; Solvents ; chemistry

Objective To investigate whether transcatheter renal sympathetic denervation (RSD) by radiofrequency ablation interfere with the development of left ventricular (LV) mechanical dyssynchrony during the progression of heart failure (HF).Methods Nineteen beagles were randomly divided into sham-operated group (six dogs),control group (seven dogs),and RSD group (six dogs).Sham-operated group were implanted with pacemakers without pacing;Control group were implanted with pacemakers and underwent 3 weeks of rapid right ventricular pacing;and RSD group underwent catheter-based RSD bilaterally and were simultaneously implanted with pacemakers.LV dyssynchrony was analyzed via 2D speckle-tracking strain echocardiography to evaluate LV function.Longitudinal dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain on apical 4-and 2-chamber views.Radial and circumferential dyssynchrony was determined as the standard deviation for time-to-peak speckle-tracking strain in mid-and base-LV short-axis views.LV systolic pressure (LVSP) and LV end-diastolic pressure (LVEDP) were measured.The LV interstitial fibrosis was determined by histological analysis.Results After 3 weeks,all of the dogs in both the control and RSD groups showed greater LV end-diastolic volume compared with the sham-operated group;however,the dogs in the RSD group had a higher LV ejection fraction (LVEF) than the dogs in the control group (P ＜0.001).The LV systolic strains were higher in the RSD group than in the control group (P ＜0.001 for longitudinal,circumferential and radial strain,respectively).The levels of LV dyssynchrony were lower in the RSD group than in the control group (P ＜ 0.001 for longitudinal,circumferential and radial dyssynchrony,respectively).Compared with control group,RSD group had lower LV end-diastolic pressures and less fibrous tissue.Conclusions RSD inhibites the development of left ventricular mechanical dyssynchrony during the progression of heart failure in dogs.

Objective To investigate the effect of tMfn2 gene on inhibiting the proliferation of vascular smooth muscle cells (VSMCs) and related mechanism. Method VSMCs were transfected with adenovirus vector encoding tMfn2 or Mfn2 (Adv-tMfn2, Adv-Mfn2). The abundance of tMfn2 protein and Mfn2 protein were deter-mined by Western blot analysis using Mfn2 N-term antibody. The effect of tMfn2 on the proliferation of VSMCs was explored by cell counting and MTT assay. The cell cycle was analyzed using flow cytometry. Western blot were used to detect the expression of p-ERK1/2 and p-Raf-1. Results The results of cell counting and MTT both indi-cated that tMfn2 gene displayed more remarkable effect on inhibiting the proliferation of VSMCs than Mfn2 (P <0.01). Flow cytometry showed that most of the cells infected with Adv-tMfn2 or Adv-Mfn2 were blocked in the stage of G0/G1 and few entered into the S phase. Western blot indicated that overexpression of tMfn2 gene resulted in downregulation of phosphorylated ERK1/2 and Raf-1 protein (P < 0.01). These results demonstrated tMfn2 had stronger effect than Mfn2 (P < 0.01). Conclusions tMfn2 gene is superior to Mfn2 gene in attenuating the proliferation of VSMCs via the Ras-Raf-ERK1/2 signaling pathway.

It is crucial to improve the health care quality during the progress of constructing the new health care system in both urban and rural area.On the condition of increasing government commonweal investment for the basic health care,the standardized training program for the district medical practitioners will become the pivotal step to improve district health care in urban and rural area,standardize medical service,reduce the medical cost and optimize the accessibility to medical care for the mass.Taking the consideration on the personal resource of district medical service in the urban and rural area in China,certain strategic proposals related to the standardized training program for the fundamental medical practitioners are discussed.